Saand Mumtaz A, Xu You-Ping, Li Wen, Wang Ji-Peng, Cai Xin-Zhong
Institute of Biotechnology, College of Agriculture and Biotechnology, Zhejiang University Hangzhou, China.
Centre of Analysis and Measurement, Zhejiang University Hangzhou, China.
Front Plant Sci. 2015 May 5;6:303. doi: 10.3389/fpls.2015.00303. eCollection 2015.
The cyclic nucleotide gated channel (CNGC) is suggested to be one of the important calcium conducting channels. Nevertheless, genome-wide identification and systemic functional analysis of CNGC gene family in crop plant species have not yet been conducted. In this study, we performed genome-wide identification of CNGC gene family in the economically important crop tomato (Solanum lycopersicum L.) and analyzed function of the group IVb SlCNGC genes in disease resistance. Eighteen CNGC genes were identified in tomato genome, and four CNGC loci that were misannotated at database were corrected by cloning and sequencing. Detailed bioinformatics analyses on gene structure, domain composition and phylogenetic relationship of the SlCNGC gene family were conducted and the group-specific feature was revealed. Comprehensive expression analyses demonstrated that SlCNGC genes were highly, widely but differently responsive to diverse stimuli. Pharmacological assays showed that the putative CNGC activators cGMP and cAMP enhanced resistance against Sclerotinia sclerotiorum. Silencing of group IVb SlCNGC genes significantly enhanced resistance to fungal pathogens Pythium aphanidermatum and S. sclerotiorum, strongly reduced resistance to viral pathogen Tobacco rattle virus, while attenuated PAMP- and DAMP-triggered immunity as shown by obvious decrease of the flg22- and AtPep1-elicited hydrogen peroxide accumulation in SlCNGC-silenced plants. Additionally, silencing of these SlCNGC genes significantly altered expression of a set of Ca(2+) signaling genes including SlCaMs, SlCDPKs, and SlCAMTA3. Collectively, our results reveal that group IV SlCNGC genes regulate a wide range of resistance in tomato probably by affecting Ca(2+) signaling.
环核苷酸门控通道（CNGC）被认为是重要的钙传导通道之一。然而，尚未对作物物种中的CNGC基因家族进行全基因组鉴定和系统功能分析。在本研究中，我们对经济作物番茄（Solanum lycopersicum L.）中的CNGC基因家族进行了全基因组鉴定，并分析了IVb组SlCNGC基因在抗病性中的功能。在番茄基因组中鉴定出18个CNGC基因，并通过克隆和测序纠正了数据库中4个错误注释的CNGC位点。对SlCNGC基因家族的基因结构、结构域组成和系统发育关系进行了详细的生物信息学分析，并揭示了其组特异性特征。综合表达分析表明，SlCNGC基因对多种刺激具有高度、广泛但不同的响应。药理学分析表明，假定的CNGC激活剂cGMP和cAMP增强了对核盘菌的抗性。沉默IVb组SlCNGC基因显著增强了对真菌病原体瓜果腐霉和核盘菌的抗性，强烈降低了对病毒病原体烟草脆裂病毒的抗性，同时减弱了PAMP和DAMP触发的免疫反应，如在SlCNGC沉默植株中flg22和AtPep1诱导的过氧化氢积累明显减少所示。此外，沉默这些SlCNGC基因显著改变了一组钙信号基因的表达，包括SlCaMs、SlCDPKs和SlCAMTA3。总的来说，我们的结果表明，IV组SlCNGC基因可能通过影响钙信号来调节番茄中的多种抗性。
